The focus of this research will be to evaluate vertically-aligned carbon nanofiber (VACNF) arrays as a parallel interface to deliver macromolecules, specifically different DNAs, in a spatially resolved manner to cellular matrices. Our nanofiber-based approach exploits a universal delivery mechanism, microinjection, that has been demonstrated as effective for all cell types (mammalian, plant, bacterial). However, unlike conventional microinjection, which is a labor intensive and slow serial method for single cell delivery, vast arrays of VACNFs can provide for massively parallel gene delivery to cellular matrices. Spatially resolved delivery will allow the production of arrays of genetically manipulated live cells that can be used as a powerful discovery tool. Examples of applications and future R01 efforts that can be supported by successful demonstration of this tool include the real-time functional characterization of large ensembles of expressed gene products, the evaluation of specificity of candidate drugs on libraries of over-expressing transformed cells, and loss-of-function analyses in cell groups receiving or producing interfering RNAs. Towards this goal, this effort will evaluate the potential of nanofiber-mediated gene delivery, with the specific target of spatially resolved material delivery to cellular matrices for live-cell arraying. In this R21 effort we will: 1. Investigate strategies for temporarily and permanently immobilizing different DNAs in discrete patterns to localized regions of periodic arrays of vertically-aligned carbon nanofibers grown on planar substrates 2. Incorporate these DNA-modified arrays into cellular matrices in a parallel 'microinjection'-based scheme and subsequently quantify the effectiveness of plasmid delivery and expression within targeted cells. 3. Initially evaluate nanofiber-mediated methods for live cell microarraying of diverse cell types; including both mammalian and yeast cells.